SQL - How to get Count, Group by based on Like Message

create table #t 
(
    BillId int,
    StepName varchar(100),
    StepExec varchar(100),
    StepExecResult varchar(100),
    Created_date datetime
)

insert into #t 
values
    (1, 'Initiated', 'Taken Place','Pass', getdate()-10),
    (1, 'POS', 'Deadlock Error','Error', getdate()-9),
    (1, 'POS', 'Processed','Pass', getdate()-9),
    (1, 'Merchandise', 'Taken Place','Pass', getdate()-8),
    (1, 'verification', 'Webservice call error','Error', getdate()-7),
    (1, 'verification', 'Webservice call error','Error', getdate()-6),
    (1, 'verification', 'Webservice call','Pass', getdate()-5),
    (1, 'verification', 'Webservice Response','Error', getdate()-5),
    (1, 'verification', 'Webservice Response','Pass', getdate()-5),
    (1, 'verification', 'Timeout Error','Error', getdate()-5),
    (1, 'verification', 'Timeout Error','Error', getdate()-5),
    (1, 'verification', 'Timeout Error','Error', getdate()-5),
    (1, 'verification', '','Pass', getdate()-5),
    (1, 'Payment', 'calculationError','Error', getdate()-4),
    (1, 'Payment', 'calculationProcessed','Pass', getdate()-3),
    (1, 'Completed', 'Archived','Pass', getdate()-1),
    (2, 'Initiated', 'Taken Place','Pass', getdate()-10),
    (2, 'POS', 'Deadlock Error','Error', getdate()-9),
    (2, 'POS', 'Processed','Pass', getdate()-9),
    (2, 'Merchandise', 'Taken Place','Pass', getdate()-8),
    (2, 'verification', 'Webservice call error on 07/23/2016','Error', getdate()-7),
    (2, 'verification', 'Webservice call error on 07/24/2016','Error', getdate()-6),
    (2, 'verification', 'Webservice call','Pass', getdate()-5),
    (2, 'verification', 'Webservice Response','Error', getdate()-5),
    (2, 'verification', 'Webservice Response','Pass', getdate()-5),
    (2, 'verification', '','Pass', getdate()-5),
    (2, 'Payment', 'calculationProcessed','Pass', getdate()-3),
    (2, 'Completed', 'Archived','Pass', getdate()-1)

select 
    stepname, count(*) as ErrorCount 
from 
    #t
where 
    StepExecResult = 'Error'
group by 
    stepname


	SELECT  StepName ,
        SUM(COUNT(DISTINCT BillId)) OVER (PARTITION BY StepName) TotalStepError,
        StepExec ,
        COUNT(DISTINCT BillId) ErrorTypeCount
FROM    #t
WHERE   StepExecResult = 'Error'
GROUP BY StepName,
        StepExec


StepName	TotalStepError	StepExec			ErrorTypeCount
----------------------------------------------------------------
Payment			1			calculationError		1
POS				2			Deadlock Error			2
verification	6			Timeout Error			1
verification	6			Webservice call error	3
verification	6			Webservice Response		2